Heirarchal organizations:

• proteins, organic compounds -> organelles -> cells -> tissues -> organs -> individual organisms -> populations -> ecosystems -> biosphere
• ions -> ionic groups -> minerals -> rocks -> geologic units -> mountain belts, sedimentary basins -> lithosphere (crust, mantle, core) -> planet -> planetary system.
• above will be approach we will take for awhile.

Review of atomic architecture.

• electrons, neutrons, protons, nucleus, electron shells.
• What controls how different atoms/ions combine together?
• What are isotopes and why they are important?

Elemental make-up of earth's crust:

• by weight - O2 47.2%, Si at 28.2%, Al at 8.2%, Fe at 5.1%.
• chemistry as language and the periodic chart alphabet.
• silicates - the most common mineral type, all have in common the silicate tetrahedra ionic group.
• 
• Above is a diagram of the basic building block (ionic group) of the majority of minerals that compose the earth.
• note that sometimes an Al ion can substitute for the Si in the center.

What determined the chemical make-up of the earth?

Definition of a mineral: solid/crystalline (regular atomic architecture), inorganic, naturally occurring, fixed or limited range of chemical composition.

What are diagnostic properties for hand specimen identification?

Atomic architecture and the relation to hand specimen diagnostic properties:

• Simple examples - halite (NaCl)3 and graphite (C6) and calcite (CaCO3).
• For silicates the key is that tetrahedra join to form larger units by joining of corners, by the sharing of the corner oxygen ion. A useful metaphor is of anion silicate bricks and cation glue.
• Silicate structural families - sheet silicates (micas) and the chain silicates (amphiboles and pyroxenes)

Rhyme or reason to the various types of silicate minerals? One organizing factor is the number of tetrahedral oxygen that are shared.

• sorosilicates (isolated tetrahedra), no oxygen shared, e.g. olivine.
• single chain silicates, 2 out of four oxygen shared, e.g. pyroxene.
• double chain silicate, 2.5 our of four oxygen shared, e.g. amphiboles.
• sheet silicate, 3 out of oxygen shared, micas of all sorts.
• framework silicates, all 4 oxygen shared, quartz, and feldspar.
• less sharing to more sharing = olivine -> pyroxene -> ampiboles -> mica -> quartz, feldspar. We will see this series of minerals again! This represents something fundamental.

Solid substitution series in minerals (remember that "limited range of chemical composition" in the definition of whats a mineral).

• Mg+2 - .66
• Fe+2 - .74
• Fe+3 - .64

  ---

• Si+4 - .40
• Al+3 - .49

  ---

• examples (there are many):
• the substitution is designated by "(X, Y)" where X and Y substitute for each other
  • olivine (Mg,Fe)2 SiO4
  • plagioclase series (Ca,Na) (Al,Si) Al Si2O8
    • paired solid substitution series.
• What determines the exact composition of an individual mineral?
  

Information in mineral textures:

• zonation
• exsolution intergrowth
• crystal form
• fluid inclusions
• some images

Non-silicate mineral groups and their economic importance:

• oxides: magnetite Fe3O4, hematite Fe2O3, gibbsite Al2O3 X (OH)
• sulfides: pyrite FeS chalcopyrite (Fe,Cu) S, sphalerite ZnS, galena PbS
• native elements: gold and copper
• carbonates: calcite and aragonite CaCO3, dolomite (Ca, Mg)CO3
• evaporites: halite - NaCl, sylvite KCl, gypsum CaSO4 H2O
  

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